/**
 * Sidebar Layout Component
 * Modern sidebar navigation with glassmorphism effects
 * Following BEM (Block Element Modifier) methodology
 */

/* ========================================
   Sidebar Block
   ======================================== */
.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: var(--sidebar-width);
    height: 100vh;
    background: linear-gradient(180deg, var(--color-dark) 0%, var(--color-darker) 100%);
    color: var(--color-white);
    overflow-x: hidden;
    overflow-y: auto;
    box-shadow: 4px 0 24px rgba(0, 0, 0, 0.12);
    z-index: var(--z-index-dropdown);
    transition: transform var(--transition-base) var(--ease-out);
}

/* Scrollbar Styling */
.sidebar {
    /* Firefox */
    scrollbar-width: thin;
    scrollbar-color: rgba(255, 255, 255, 0.2) transparent;
}

.sidebar::-webkit-scrollbar {
    width: 6px;
}

.sidebar::-webkit-scrollbar-track {
    background: transparent;
}

.sidebar::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-sm);
}

.sidebar::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.3);
}

/* ========================================
   Sidebar Content
   ======================================== */
.sidebar__content {
    display: flex;
    flex-direction: column;
    height: 100%;
    padding: 0;
}

/* ========================================
   Sidebar Header
   ======================================== */
.sidebar__header {
    padding: var(--space-8) var(--space-6) var(--space-6);
    text-align: center;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    background: rgba(0, 0, 0, 0.1);
}

.sidebar__logo-link {
    display: block;
    text-decoration: none;
    color: var(--color-white);
    transition: transform var(--transition-base) var(--ease-out);
}

.sidebar__logo-link:hover {
    transform: scale(1.02);
}

.sidebar__logo {
    height: 60px;
    width: auto;
    filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.3));
    transition: filter var(--transition-base) var(--ease-out);
}

.sidebar__logo-link:hover .sidebar__logo {
    filter: drop-shadow(0 6px 12px rgba(0, 0, 0, 0.4));
}

/* ========================================
   Sidebar Menu
   ======================================== */
.sidebar__menu {
    flex: 1;
    padding: var(--space-4) 0;
    overflow-y: auto;
}

.sidebar__nav {
    padding: 0;
    list-style: none;
}

.sidebar__nav-item {
    margin: 0;
}

.sidebar__nav-link {
    display: flex;
    align-items: center;
    padding: var(--space-3) var(--space-6);
    color: rgba(255, 255, 255, 0.75);
    text-decoration: none;
    font-weight: var(--font-weight-medium);
    font-size: var(--font-size-sm);
    border-left: 3px solid transparent;
    transition: color var(--transition-base) var(--ease-out),
                background-color var(--transition-base) var(--ease-out),
                border-left-color var(--transition-base) var(--ease-out);
}

.sidebar__nav-link:hover {
    color: var(--color-white);
    background: rgba(255, 255, 255, 0.07);
    border-left-color: rgba(var(--color-primary-rgb), 0.5);
}

.sidebar__nav-link--active {
    color: var(--color-white);
    background: rgba(var(--color-primary-rgb), 0.22);
    border-left-color: var(--color-primary);
    font-weight: var(--font-weight-semibold);
}

.sidebar__nav-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 20px;
    height: 20px;
    margin-right: var(--space-3);
    font-size: var(--font-size-base);
    transition: color var(--transition-base) var(--ease-out);
}

.sidebar__nav-link--active .sidebar__nav-icon {
    color: var(--color-primary);
}

.sidebar__nav-text {
    flex: 1;
    position: relative;
    z-index: 1;
}

/* Navigation Divider & Section Labels */
.sidebar__nav-divider {
    list-style: none;
    padding: var(--space-5) var(--space-6) var(--space-1);
    margin-top: var(--space-2);
}

.sidebar__nav-divider:first-child {
    margin-top: 0;
    padding-top: var(--space-1);
}

.sidebar__nav-section-label {
    display: block;
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-gray-500);
}


/* ========================================
   Sidebar Close Button (Mobile)
   ======================================== */
.sidebar__close-btn {
    display: none;
    position: absolute;
    top: var(--space-4);
    right: var(--space-4);
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border: none;
    border-radius: var(--radius-md);
    color: var(--color-white);
    font-size: var(--font-size-2xl);
    cursor: pointer;
    align-items: center;
    justify-content: center;
    transition: background-color var(--transition-base) var(--ease-out);
    z-index: 1001;
}

.sidebar__close-btn:hover {
    background: rgba(var(--color-primary-rgb), 0.3);
}

/* ========================================
   Layout Adjustments
   ======================================== */
@media (min-width: 992px) {
    body:not(.no-sidebar) {
        padding-left: var(--sidebar-width);
    }
}

@media (max-width: 991.98px) {
    body {
        padding-left: 0;
    }

    /* Default: sidebar is off-screen on mobile, but always above navbar */
    .sidebar {
        transform: translateX(-100%);
        z-index: var(--z-index-fixed);
    }

    /* Open state: slide in */
    .sidebar--open {
        transform: translateX(0);
        border-right: 1px solid rgba(255, 255, 255, 0.12);
    }

    .sidebar__close-btn {
        display: flex;
    }

    .sidebar__header {
        padding: var(--space-6) var(--space-4);
    }

    .sidebar__logo {
        height: 48px;
    }

    .sidebar__nav-link {
        padding: var(--space-3) var(--space-4);
    }

    .sidebar__nav-icon {
        margin-right: var(--space-3);
    }
}

/* ========================================
   Mobile Overlay (managed by JS)
   ======================================== */
.sidebar-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: calc(var(--z-index-fixed) - 1);
}

.sidebar-overlay--visible {
    display: block;
}

/* ========================================
   Focus States for Accessibility
   ======================================== */
.sidebar__nav-link:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: -2px;
}

.sidebar__logo-link:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 4px;
    border-radius: var(--radius-base);
}

.sidebar__close-btn:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* ========================================
   Reduced Motion
   ======================================== */
@media (prefers-reduced-motion: reduce) {
    .sidebar,
    .sidebar__nav-link,
    .sidebar__nav-icon,
    .sidebar__logo-link,
    .sidebar__logo,
    .sidebar__close-btn {
        transition: none;
    }
}